GUIDELINES FOR APPLYING CONTENT DESIGNATORS

Content designators identify the subelements occurring in topical term and node label
headings constructed according to generally accepted thesaurus-building conventions
(e.g.,
Library of Congress Subject Headings). Topical terms include occupation and
function terms that are used as the lead element of subject or added entry access
fields in
bibliographic records. A topical term that is authorized for use only as a
subject subdivision part of an extended subject heading is contained in a 180
(General
Subdivision) or 182 (Chronological Subdivision) field.

■ INDICATORS

First Indicator - Undefined

Undefined and contains a blank (#).

Second Indicator

In fields 150, 450, and 550, the second indicator position is undefined and contains
a
blank (#). For field 750, the second indicator position contains one of the
values
described in the 7XX Heading Linking Entries-General Information section.

■ SUBFIELD CODES

$a - Topical term or geographic name entry element

Topical subject, a geographic name used as an entry element for a topical term, or
a
node label term. Parenthetical qualifying information is not separately subfield
coded.

150

##$aBlood

150

##$aCatalogs by source

150

##$aCharacters and characteristics in literature

150

##$aBull Run, 2nd Battle of, Va., 1862

450

##$aCaracas.$bBolívar Statue[Example of a non-LCSH topical see from tracing.]

$b - Topical term following geographic name entry element

Topical term that is entered under a geographic name contained in subfield $a. This
construction is not commonly used in 150 or 550 heading fields; it may occur
in 450 See
From Tracing fields.

450

##$aWashington (D.C.)$bLincoln Memorial

$g - Miscellaneous information

Data element that is not more appropriately
contained in another defined subfield.

150

##$aUntergrund$gBodenkunde

150

##$aUntergrund$gPolitik[Examples in German of two different entities sharing the same word as their name]

$i - Relationship information [450/550/750]

Designation of a relationship of the entity in a 450, 550, or 750 field to the
1XX entity in the record or a textual reference instruction phrase. For fields 450 and 550 the phrase
may be system-generated from the field tag or from the codes
defined for subfield $w (Control subfield). Subfield $i is appropriate
only in fields 450, 550, and 750. Guidelines for using subfield $i in fields 450 and 550 are
provided in the Tracings and References-General
Information section. Guidelines for using subfield $i in field 750 are
provided in the 7XX Heading Linking Entries-General Information section.

$v - Form subdivision

Designates a specific kind or genre of material as defined by the thesaurus being
used.
Subfield $v is appropriate in the X50 fields only when a form subject subdivision
is
added to a main term to form an extended heading.

150

##$aScuba diving$vPeriodicals

$w - Control subfield [450/550/750]

Codes in one or more character positions defined to control the display of information
and specify relationships, restrictions, and status. Subfield $w is appropriate
only in
field 450, 550, and 750. Character position definitions and guidelines for applying
the
codes defined for subfield $w in field 450 and 550 are provided in the Tracings and References-General
Information section. Character position definitions and
guidelines for field 750 are provided in the 7XX Heading Linking Entries-General
Information section.

$x - General subdivision

Subject subdivision that is not more appropriately contained in subfield $v (Form
subdivision), subfield $y (Chronological subdivision), and subfield $z (Geographic
subdivision). Subfield $x is appropriate in the X50 fields only when a general
topical
subject subdivision is added to a main term to form an extended heading.

150

##$aConflict of laws$xSupport (Domestic relations)

150

##$aExecutives$xSalaries, etc.

150

##$aAmusements$xReligious aspects$xBuddhism, [Christianity, etc.]

$y - Chronological subdivision

Subject subdivision that represents a period of time. Subfield $y is appropriate in
the
X50 fields only when a chronological subject subdivision is added to the main
term to
form an extended heading.

150

##$aArchitecture, Modern$y19th century

150

##$aGod$xHistory of doctrines$yMiddle Ages, 600-1500

150

##$aMusic$y500-1400

150

##$aPainting, Chinese$ySung-Yüan dynasties, 960-1368$xSocieties, etc.

$z - Geographic subdivision

Appropriate in the X50 fields only when a geographic subject subdivision is added
to a
main term to form an extended heading.

Code that identifies the source of a heading or term when the second indicator position
contains value 7. Subfield $2 is appropriate only in field 750. Guidelines for
applying
subfield $2 are provided in the 7XX Heading Linking Entries-General
Information
section.

INPUT CONVENTIONS

Punctuation - Punctuation of the subelements of a heading is generally dictated by subject heading
system/thesaurus rules. These input conventions clarify MARC punctuation practices.
An X50
field does not end with a mark of punctuation unless the field ends with an abbreviation,
an
initialism, or data that ends with a mark of punctuation.

150

##$aMagazine illustration

150

##$aSeasonal variations (Economics)

150

##$aEducation$zWashington (D.C.)

150

##$aMuseums$zRussia (Federation)

150

##$aArt, Chinese$yTo 221 B.C.

150

##$aResearch libraries$zMexico$xSocieties, etc.

Spacing - No spaces are used in initialisms, acronyms, or abbreviations.

150

##$aC.O.D. shipments

450

##$aB.A. degree

One space is used between preceding and succeeding initials if an abbreviation consists
of
more than a single letter.

450

##$aPh. D. degree

Display Constant

-

[dash associated with the content of subfield $v, $x, $y, and $z]

Dash (-) that precedes a subject subdivision in an extended subject heading is not
carried
in the MARC record. It may be system generated as a display constant associated
with the
content of subfield $v, $x, $y, and $z.